1. Field of the Invention
The invention is concerned with thermoplastic bag construction, and more particularly the construction of bags to be supplied in multiple bag packs wherein the bags are interlocked by severable tabs which allow for a separate dispensing of the individual bags. Such bags normally incorporate integral handles and are mountable on a dispensing rack by the tabs with the individual bags being detached from the tabs and the pack by physically pulling the bag from the rack.
The bags are frequently formed of flattened tube portions selectively severed from a length of tubing of appropriate material and subsequently heat sealed along the upper and lower edges thereof. An appropriate mouth-defining U-shaped cutout is normally made through the sealed upper edge, the cutout simultaneously defines opposed handles. The known bags have been formed both with and without side gussets.
2. Description of the Prior Art
Typical examples of the known prior art will be seen in the following patents: U.S. Pat. No. 3,352,411 Schwarzkopf; U.S. Pat. No. 3,774,838 Christie; U.S. Pat. No. 4,062,170 Orem; U.S. Pat. No. 4,165,832 Kuklies et al; U.S. Pat. No. 4,199,122 Christie.
Schwarzkopf illustrates a basic bag construction wherein a partially severed U-shaped flap forms a detachable tab. Upon separation of the bag from the flap, two integral handles are formed. The partially severed flap constitutes the means by which the bag is mounted in a pack and on a dispensing rack.
The patent of Kuklies et al discusses the general nature of the known art, as exemplified by the Schwarzkopf patent, and proposes modifications in the handle configuration, the configuration of the bag mouth, and the nature of the detachable tab. Basically, Kuklies et al provides a handle and mouth arrangement which includes an enlarged projecting detachable tab fixed centrally along the mouth by a perforated or tear area, the opposed ends of the mouth incorporating downwardly enlarged arcuate notches commencing at the handles and terminating at the tab. These notches are indicated as being for stress relief. Upon removal of the Kuklies bag from the mounting tab, the mouth of the bag is defined, along each bag wall, by a central upwardly projecting flap with a perforation-defined edge and opposed enlarged end notches. The projecting flap and perforation edge, in the high stress area of the bag mouth, form areas of potential difficulty.
Both Christie U.S. Pat. No. 4,199,122 and Orem disclose racks for stacks of handle bags. The bags in Orem include detachable perforated tabs along the mouth-defining upper edges of the bag walls.
Christie U.S. Pat. No. 3,774,838 discloses a plastic bag with integral tie portions.